FRIDAY, Sept. 27 (HealthDay News) -- Healthy eating habits can significantly reduce high blood pressure and improve heart function in heart failure patients, a new study says.

The study included patients, most in their 60s and 70s, who ate only meals that were prepared for them in the kitchen of the University of Michigan Clinical Research Unit.

The meals, which could be picked up and heated at home, followed the DASH (Dietary Approaches to Stop Hypertension) diet eating plan, which is high in potassium, magnesium, calcium and antioxidants. The diet is recommended for high blood pressure treatment by the American Heart Association and the U.S. National Institutes of Health.

The diet used in the study also contained a daily sodium intake of 1,150 milligrams or less, which is much lower than American adults' typical intake of about 4,200 mg a day for men and 3,300 a day for women.

After three weeks of following this diet, patients saw a drop in blood pressure similar to that achieved by taking blood pressure medications, according to the study presented Tuesday at a Heart Failure Society of America meeting.

"Our work suggests diet could play an important role in the progression of heart failure, although patients should always talk to their doctor before making major dietary changes," Dr. Scott Hummel, a cardiologist at the University of Michigan Frankel Cardiovascular Center, said in a university news release.

"We're excited to confirm these results in longer-term studies that also help us understand the challenges patients face when they try to improve their eating habits," he added.

Heart failure means the heart can't pump enough blood to meet the body's needs.

Doctors have long known that the low-sodium DASH diet can lower blood pressure in patients who are sensitive to salt. This study, although small, showed that the DASH diet can improve left ventricular relaxation and reduce diastolic chamber stiffness in heart failure patients, meaning a more efficient transfer of blood between the heart and arteries, Hummel explained.

Data and conclusions presented at meetings should be considered preliminary until published in a peer-reviewed medical journal.

More information

The U.S. National Heart, Lung, and Blood Institute has more about the DASH diet.